Native ad critics usually harp on the scale issue. Outside of platforms, the argument goes, true native formats that adapt to their environments don’t scale because they’re custom by definition. A growing collection of startups, including companies like Nativo, Sharethrough and Publish2, are attempting to fix that with what are essentially ad networks for sponsored content. The irony is these companies are following a trail blazed long ago by those who helped the banner ad itself scale into a mass media option. Article continues at digiday.com